Metal-extruding tool



June 8 1926.

, c. E.LYMAN METAL EXTRUDING TOOL ,Filed Nov. 25 1924 2 Sheets-Sheet LKMQ June 8 1926.

1,588,246 C. E. LYMAN METAL EXTRUDING TO OL Patented June 8, 1926.

PATENT OFFICE.

. CHARLES E. LYMAN, OF WATERBURY, CONNECTICUT.

METALEXTRUDING Toor..

Application led November This invention relates to those tools which are used in metal heading machines, punch presses and the like machine tools for f orming from rod, wire or slugs, socketed pleces, such as nipples, socketed rivets, set screws with socketed heads and a great variety of articles having recesses and which previously have been merely punched or drawn from blanks into shape.

The object of the present invention is to,

so construct the tools used in machines of the class referred to that large numbers of articles of Various shapes and sizes having. deep holes `may be rapidly formed in a single, simple operation, with a consequent saving of material, time and labor, by the ordinary heading or swedging machines in common use, and thereby materially reducing the cost of production of such articles.

This object is attained by providing a punch pin having the required cross section shape` and length to produce f the desired socket in the article, Vand a co-operating sliding die with an opening which will'give the required exterior conformation to the article, the co-action of these being such that the punch pin enters the die and the met-al of the blank is extruded around the punch as on a mandrel, .the die retreating coincidently with the advance of the lpin so that the effective area of the die wall will always be the same, depending of course on the kind of metal used.

The tools illustrated and described herein are designed more especially for a cold process heading machine of the type set forth in United States patent to Campbell #569,406, October 13, 1896, and Fig. 1 of the drawings shows so much of such a machine as is necessary to an understanding of the invention. Fig. 2 shows, on larger scale, a face view of the ram slide carrying the feed pin, punch and ejector. Fig. 3 is a section of the punch,

and die in their normal relation. Fig. 4 is a section of the die with a blank fed into it by the feed pin. Fig. 5 is a view showing the punch pin advanced and about to enter the blank. Fig. 6 is a similar view showing the relations of the parts with the punch pin in the blank, the die pressed back and the metal of the blank formed around the pin. Fig. 7 is a section of the die containing a blank and the end of the punch pin, indicating the ef- 25, 1924. serial N. 752,161.'

solid die cold heading machine of welly known construction. This slide is carried forward and backward with the ram and at the proper times is vertically reciprocated in the usual manner. The punch bed 2 is attached to the face of the slide and has a recess containing a hollow punch holder 3, a plate 4 holding the punch pin 5 and a hardened plate 6 backing the punch pin. The punch pin may have a round, square or hex'-v agonal cross section, depending on the desired shape of the socket to be formed. In the punch holder is a sliding sleeve 7 which is employed to support and guide the punch pin and also to strip the finished piece from the pin. The position of this sleeve is controlled by a forked stud 8 connected with a lever 9 that is pulled forward as the punch recedes by a rod 10 and is pressed back as the punch advances by a 'spring 11. The punch slide also carries a forwardly pressed spring pin 12 that is employed to push the blank 13 intov the die, these parts and their.

action being well known to those familiar with this class of machines are consequently not illustrated and described in more detail.

The die block 14 is fixed to the-inner face of the end wall 15 of the main frame of the machine. In a recess inthe die block is a fixed sleeve 16. The die 17 is slidably 'fitted in the sleeve and is normally pressed forward by a spring 18. The die opening has the necessary cross sectional shape to form the required exterior shape of the article to be produced. .Projecting into the die opening is a pin 19 at the end of the knock-out plunger 20.. The length of this pin is varied according to the length of the blank to be operated upon.

With the parts in their normal positions and doing no work the die 17 is pressed for- Ward by its sprin and the forwardend of the pin 19 is a litt e inside of theface of the die, while the forward end of the punch pin standard two-blow header for which these tools are especially designed the blank that is slightly smaller than the die cavity, is fed in the usual way and is pushed into the die by the feed pin 12 lthat at this time is lowered into line with the die. As this takes placev the pin 19 and knock-out plunger 20 are forced back, as illustrated in Fig. 4f. After the feed pin is Withdrawn and raised and the punch brought into line with theI die the punch is moved forward. As the punch reaches the die the face of the punch engages the face of the die and the guiding sleeve 7 in the punch holder is pushed back. At this time the end of the punch pin enters the die opening and engages'the end of the blank, as shown in Fig. 5. During the continuation of the forward movement of the punch the punch holder presses back the die a distance equal to the distance that the punch pin enters the blank and the guiding sleeve at this time is equally pushed back, as illustrated in Fig. 6. As the punch pin is forced into the blank which is held bythe die and backing pin the met-al of the blank is forced out`of or extruded from the die around the punch pin. The dieis moved back a distanceequal to the amount of movement of the punch pin, consequently the area ofthe wall of the die cavity which controls the shape of the metal extruded is always the same, and this varea is proportional to the distance that the punch pin extends into the die opening. In the form illustrated this distance is equal to the distance between the two dotted lines shown in Fig. 7, which may be very small as it is the mouth of the cavity which .gives the exterior shapeto the metal, and this shape once given remains.

It is essential that the die move inward in,

the manner described so that the friction of the metal being extruded on the wall of the -die cavity is always t-he same. It is also essential that the punch pin enter the die cavity before it begins to act on the blank. As the pin presses against the blank the metal is caused to How in the line of least resistance which is outward from the die cavity around the pin that then acts as a mandrel as Well as a punch.

The invention claimed is:- X

. 1. Tools for forming socketed metal pieces comprising a fixed die holder, a die slidably fitted within the die holder and having 'a cavity shaped to give t-he exterior conforma.- tion to the pieces, means normally pressing the die forward in the die holder and a reciprocatory punch comprising a punch holder and a in tliat is smaller in cross section than t e cross section of the die cavity and shaped'to impart the interior outline to, the socket, said pin projecting slightly beyond the face of the punch holder and said punch holder being adapted to engage and press back the die, after said pin has entered the die cavity and engaged'the pieces to be socketed, a distance equal tothe distance the pin enters the pieces.

2. Tools for forming socketed metal pieces comprising a fixed die holder, a die slidably fitted Within the die holder and having a cavity shaped to give the exterior conformatio-n to the pieces, a spring for forcing said die forward, and a reciprocatory punch comprising a punch holder and a pin thatis smaller in cross vsection than the cross section of the die cavity and shaped to imparty fitted within the. die holder and having a cavity shaped to give the exterior conformation to the pieces, means normally pressing the die forward in the die holder a backing and knock-out pin extending into the die cavity, and a reciprocatory punch comprising a punch holder and a pin that is smaller in cross section than the. cross section ofthe die cavity and shaped to Iimpart the interior outline to the socket, said pinl projecting slightly beyond the face of the punch holder and said punch holder being adapted to engage and press back the die, after said pin has entered the die cavity and engaged the pieces to b'e socketed, a distance equal to the distance the pin enters the pieces.

4. Tools for forming socketed metal pieces comprising a fixed die holder, a die slidably fitted within the die holder and having ar cavity shaped to give the exterior conformation to the pieces, means normally pressingv the die forward in the die holder a reciprocatory punch comprising a punch holder and a pin that is smaller in cross section than the cross section of the die cavity and shaped to impart the interior outline to the socket, said pin projecting slightly beyond the face of the punch holder and said punch holder being adapted to engage and press back the die after said in has entered the die cavity, and a sleevel s idably fitted on said pin and adapted to support the pin and also strip the piece formed by the cpo-action ofv the punch and die from the pin.

5. Tools for forming socketed metal pieces comprising a fixed die holder, a die slidably fitted Within the die holder and having a cavity `shaped to give the exterior conformation to the pieces, means normally pressing the die forward in the die holder,.and a eciprocatory punch comprising a punch holder and a pin that is smaller i-n cross ils cavity and shaped to impart the interior outline to the. socket, said pin projecting slightly beyond the face of the punch holder and said punch engaging the die and both moving together in the same direction and the same distance when a socket is being v formed in a metal piece.

prising a punch holder and a pin that is smaller in cross section than the cross section of the die cavity and shaped to impart the interior outline to the socket, said pin projecting beyond the face of the vpunch Y l holder and said punch holder being adapted to engage and force the` die backward an equal distance after the pin has entered the die cavity, so that the veffective area of the A Well of the die cavity remains the same during each operation regardless of the distance of travel'of the unh pin.

v HARLES E. LYMAN. 

